Wednesday, September 12, 2012

Today marks the formal launch of Gary Taubes' new non-profit organization NuSI whose stated mission is to, "improve the quality of science in nutrition and obesity research", and whose implied mission is to prove Gary Taubes' carbohydrate hypothesis of obesity is as correct as he clearly believes it to be.

So let's for a moment presume that Gary Taubes is one hundred percent right. That what his NuSI backgrounder calls a "controversial" hypothesis,

"that the fundamental cause of overweight and obesity is the overconsumption of food in relationship to physical activity",

is truly dead wrong and that instead it's,

"the quantity and quality of the carbohydrates – plays the more critical role in both the accumulation of excess body fat and the chronic diseases that are associated with obesity"

So that means for the moment just ignore data like those from the Ewe tribe who were recorded as having an obesity rate of 0.8% despite diets that were 84% carb. Ignore the various studies that held calories constant while varying macronutrients that demonstrated weight stability. Ignore the results from Cuba's "natural experiment" in the 1990s. Ignore the folks from the National Weight Control Registry who've lost and sustained their losses with widely divergent dietary strategies. Ignore the fact that even the most low-carb positive studies demonstrate only minor differences in weight loss as compared with higher or middle of the road carb diets. Instead I want to ask you whether or not, assuming Mr. Taubes' shiny new researcher's bench is entirely, incontrovertibly, 100% right in placing blame squarely on carbohydrate consumption, would that bench-side proof actually have broadly applicable clinical utility for folks who struggle with their weight?

My bed-side says no.

That's certainly not to say that low-carb dieting doesn't help some manage their weights and health, it just means that no amount of bench-made "proof" will change the fact that low-carb dieting, for many, is far more of a restrictive diet than it is a livable, long-term lifestyle. Meaning that even if low-carb were the holy grail of diets on paper, that fact would be worthless in practice unless you happened to enjoy low-carb enough to stick with it, and judging from the folks I see regularly in my office, that's far from a given. In fact it's a very rare person that I meet who hasn't tried a low-carb diet at least once. And all of those folks? No doubt when they undertook their low-carb diets they were true believers. As far as they were concerned low-carb was to be their salvation, and many report to me having had real success losing but that they just as rapidly regained everything when they couldn't stomach living low-carb anymore. It's that last bit that makes me think that regardless of the outcomes of Mr. Taubes' new non-profit's future studies, low-carb diets aren't going to be a panacea, just as they weren't in Banting's 1860s or Atkins' 1990s.

Mr. Taubes thinks that study design is the broken paradigm that's crippling weight management. He thinks that nutritional research hasn't asked the right questions or used the right methodologies and so that's why we're mired in this mess. And while it's easy to agree with him that there have been libraries filled with poorly designed studies, as far as clinical weight management utility goes, more effectively asking or studying whether low-carb diets have better outcomes than low-fat or other diets isn't likely to help much.

Whether it's low-carb diets, low-fat diets, GI diets, middle-ground diets, vegan diets, and even bat-shit crazy diets, there are long term success stories and recurrent failures with each and every one, where the common ground to success is a person actually liking their life enough to sustain their new patterns of reduced dietary intake, and where the common ground to failure is suffering or restriction beyond an individual's capacity to enjoy their life.

And so while I don't share Mr. Taubes' view that there is one simple or predominant cause and treatment for obesity, and would in fact argue that anyone who thinks there's a singular cause for the society's weight struggles almost certainly doesn't work with actual living, breathing, human beings on their weights, I do agree that the research on what works and what doesn't work is inherently flawed. But it's a flaw that Mr. Taubes' is likely setting out to sustain and fund in that the flaw I see from my bedside is the arrogant belief that there's one right way to go and only one path to weight gain (or loss).

There's also the issue of spin. Now I appreciate you've got to tell a good story when you're trying to raise money, but given Mr. Taubes has built his empire on the notion that science has misrepresented data on obesity for decades, you'd sure hope that he wouldn't simply do the same.

Without getting into it too deeply I want to present one graph that he includes in his non-profit's backgrounder that he uses to prove his point that it's the carbs, stupid.

The graphs are meant to be very clear. Carbohydrate intake has gone up since 1971 while fat and protein have gone down, and hey look, weight's gone up too. Must be the carbohydrates, right?

But yet a deconstruction of the first graph by Evelyn over at her Carb-Sane Asylum really gets right to the meat of things with this statement when considering the graph on the left,

"looking at this data, we have the men reducing fat % from 37 to 33% while carbs rose from 42 to 49% of intake. And the women? Fat went from 38% to 33% while carbs rose from 45% to 52%. Given all the studies done where the low carb diets were "hardly low carb" according to the militant keto wing of the movement, can we at least have a wee bit of intellectual honesty here and admit that the differences in macro proportions is largely insignificant?"

What she's saying is that from a macronutrient percentage perspective, the difference between the 1970s consumption of a diet containing 45% carbs (for women) and the 2000s diet of 52% (and for men the difference between 42% and 49%) is pretty insignificant and that 1970 diets were anything but low-carb and yet our weights were so much better.

But more disingenuous is the fact that Mr. Taubes left out his arch nemesis from the graph. Calories.

Here's a graph from Stephan Guyenet that superimposes increased American calorie consumption over that graph on the right hand side of Mr. Taubes' slide.

And would you look at that. As weight rose, so too did caloric intake. Pretty much perfectly.

Sigh.

Why we're eating more is the question that needs to be answered, and while the increased consumption of highly refined carbohydrates may indeed be a player, there's zero doubt in this bed-side's mind, the game that's being played isn't one-on-one. There's no doubt it's not as simple as, "eat less, move more", and there's equally no doubt it's not as simple as just cut carbs. If either were true, everyone who wanted to be would already be skinny.

So huge props to Mr. Taubes for being such a passionate man and for truly wanting to see his theories proven - honestly, his bordering on pathological tenacity is genuinely laudable, though I wish he would hold his own spin and writing up to the same degree of scrutiny to which he holds others'. But ultimately, whereas Mr. Taubes now wants to trade in his pen for a bench and conduct research that presumably he himself won't instantaneously and churlishly deride as being useless, when it comes to clinical utility and weight management, the last thing the world needs is to believe that there's only one right way to go.

Subscribe via Email

About Me

Family doc, Assistant Prof. at the University of Ottawa, Author of The Diet Fix, and founder of Ottawa's non-surgical Bariatric Medical Institute - a multi-disciplinary, ethical, evidence-based nutrition and weight management centre. Nowadays I'm more likely to stop drugs than start them. You can also find me on Twitter and Facebook.

Creative Commons License

Disclaimer

Any medical discussion on this page is intended to be of a general nature only. This page is not designed to give specific medical advice. If you have a medical problem you should consult your own physician for advice specific to your own situation. The mission of this blog is to provide readers with critical appraisals of nutrition and weight related claims, products and policies so as to allow readers to make more informed decisions in those areas.

The author will not post anything related to any of his patients personal medical histories or circumstances without their explicit written permission.

No personal information is collected by this website. If you'd like to leave a comment on an article, you can do so on this blog's Facebook page.

This site is hosted free of charge by Google's Blogger platform and is intended not only for allied health professionals but also for interested members of the general public.

If you have any concerns feel free to email me at yonifreedhoff [{@}] gmail dot . com